One-pot synthesis of 3-(sulfonyl)-5,6,7,8-tetrahydro-4H-pyrano[3,2-c]pyridines through a cascade Michael/cyclization reaction

In this paper, a straightforward and valid three-component Michael/cyclization reaction of (E)-1-methyl-3-(arylidene)piperidin-4-ones, 2-(sulfonyl)acetonitriles, and aromatic aldehydes was explored for the preparation of potentially biologically active 3-(sulfonyl)-5,6,7,8-tetrahydro-4H-pyrano3,2-c]pyridines under mild reaction conditions. More diverse 3-(sulfonyl)-5,6,7,8-tetrahydro-4H-pyrano3,2-c]pyridine derivatives were constructed in satisfactory yields (up to 97%). The chemical structure of newly synthesized 3-(sulfonyl)-5,6,7,8-tetrahydro-4H-pyrano3,2-c]pyridines were identified with ¹H-NMR, ¹³C-NMR, and mass spectrometry analysis. The recommendable method features a simple and direct workup, easy access to initial materials, high atom utilization efficiency, high final product yields, and a wide range of substrate adaptability.